pytest-testconfig 0.2.0

Features

pytest-testconfig is a plugin to the pytest test framework used for passing test-specific (or test-run specific) configuration data to the tests being executed.

Currently configuration files in the following formats should be supported:

• YAML (via PyYAML)

• INI (via ConfigParser)

• Pure Python (via Exec)

• JSON (via JSON)

The plugin is meant to be flexible, ergo the support of exec’ing arbitrary python files as configuration files with no checks. The default format is assumed to be ConfigParser ini-style format.

If multiple files are provided, the objects are merged. Later settings will override earlier ones.

The plugin provides a method of overriding certain parameters from the command line (assuming that the main “config” object is a dict) and can easily have additional parsers added to it.

A configuration file may not be provided. In this case, the config object is an emtpy dict. Any command line “overriding” paramters will be added to the dict.

Requirements

requires pytest>=3.5.0

Installation

You can install “pytest-testconfig” via pip from PyPI:

$ python3 -m pip install pytest-testconfig

Usage

Tests can import the “config” singleton from testconfig:

from pytest_testconfig import config

By default, YAML files parse into a nested dictionary, and ConfigParser ini files are also collapsed into a nested dictionary for foo[bar][baz] style access. Tests can obviously access configuration data by referencing the relevant dictionary keys:

from pytest_testconfig import config
def test_foo():
    target_server_ip = config['servers']['webapp_ip']

Warning: Given this is just a dictionary singleton, tests can easily write into the configuration. This means that your tests can write into the config space and possibly alter it. This also means that threaded access into the configuration can be interesting.

When using pure python configuration - obviously the “sky is the the limit” - given that the configuration is loaded via an exec, you could potentially modify pytest, the plugin, etc. However, if you do not export a config{} dict as part of your python code, you obviously won’t be able to import the config object from testconfig.

When using YAML-style configuration, you get a lot of the power of pure python without the danger of unprotected exec() - you can obviously use the pyaml python-specific objects and all of the other YAML creamy goodness.

Defining a configuration file

Simple ConfigParser style:

[myapp_servers]
main_server = 10.1.1.1
secondary_server = 10.1.1.2

So your tests access the config options like this:

from pytest_testconfig import config
def test_foo():
    main_server = config['myapp_servers']['main_server']

YAML style configuration::

myapp:

servers:

main_server: 10.1.1.1 secondary_server: 10.1.1.2

And your tests can access it thus:

from pytest_testconfig import config
def test_foo():
    main_server = config['myapp']['servers']['main_server']

Python configuration file:

import socket

global config
config = {}
possible_main_servers = ['10.1.1.1', '10.1.1.2']

for srv in possible_main_servers:
    try:
        s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        s.connect((srv, 80))
    except:
        continue
    s.close()
    config['main_server'] = srv
    break

And lo, the config is thus:

from pytest_testconfig import config
def test_foo():
    main_server = config['main_server']

If you need to put python code into your configuration, you either need to use the python-config file faculties, or you need to use the !!python tags within PyYAML/YAML - raw ini files no longer have any sort of eval magic.

Command line options

After it is installed, the plugin adds the following command line flags to pytest:

--tc-file=TESTCONFIG  Configuration file to parse and pass to tests
                      [PY_TEST_CONFIG_FILE]
                      If this is specified multiple times, all files
                      will be parsed. In all formats except python,
                      previous contents are preserved and the configs
                      are merged.

--tc-format=TESTCONFIGFORMAT  Test config file format, default is
                              configparser ini format
                              [PY_TEST_CONFIG_FILE_FORMAT]

--tc=OVERRIDES        Option:Value specific overrides.

--tc-exact            Optional: Do not explode periods in override keys to
                      individual keys within the config dict, instead treat
                      them as config[my.toplevel.key] ala sqlalchemy.url in
                      pylons.

Contributing

Contributions are very welcome. Tests can be run with tox, please ensure the coverage at least stays the same before you submit a pull request.

License

Distributed under the terms of the Apache Software License 2.0 license, “pytest-testconfig” is free and open source software

Issues

If you encounter any problems, please file an issue along with a detailed description.